Resistance-coil.



No. 568,555. Patented Feb. 19, mm.

F. CUMMINGE.

RESISTANCECUIL.

(Application filed Dec. 11, 1900.

(No Model.)

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UNITED STATES PATENT OFFICE.

FRANK COMMINGE, OF PITTSBURG, PENNSYLVANIA.

RESISTANCE-COIL.

SPECIFICATION forming part of Letters Patent No. 668,555, dated February 19, 1901.

Application filed December 11, 1900. Serial No. 39,483. No model.)

.To an whom it may concern.-

Be it known that I, FRANK GOMMINGE, a citizen of the United States of America, and a resident of Pittsburg, county of Allegheny, State of Pennsylvania, have invented certain new and usefullmprovements in Resistance- Coils, of which the following isa specification, reference being had to the accompanying drawings, forming part of this specification, in which Figure l is a diagrammatic view showing the application to a high-potential current of my improved resistance-coil. Fig. 2 is a perspective view of the device, partly broken away, illustrating the winding. ,Fig. 3 is a longitudinal section showing the terminal wires. Fig. 4 is a cross-section on the line IV IV of Fig. 3. Fig. 5 is an end view.

My invention relates to means for reducing the voltage of electric currents, whereby I am enabled to utilize currents of high potential for use in electric bells, gongs, annunciators, &c., by which a light current of, say, one hundred and ten or fifty-two volts, direct or alternating, may be reduced down to a voltage suitable to the Winding of the mag nets used in such devices to ring such bells, gongs, annunciators, &c. In devices for this purpose it has been the practice to use fine wire insulated by wrapping and arranged in coils to give the desired results; but such construction is quite expensive, and my invention provides sufficient resistance in suitably-coiled wire by insulating the difierent layers from each other and properly separating the coils, together with the employment of a suitable surrounding covering or packing, whereby the wires are protected from moisture or from any possible electric contact or danger of short-circuiting.

In the construction of my invention separate series of coils 2 are wrapped around insulating-layers 3 of sheet-asbestos or other suitable insulating material, which should be, preferably, incombustible and a non-conductor of heat, and for this purpose I have found thin sheets of asbestos-paper to be well adapted and suitable for the objects in view.

In the construction of the resistancecoil the innermost sheet is first laid around a mandrel and the first layer of wire 2 is wound around it from one end to the other, leaving the terminals 4 projecting outwardly at the end where the winding is commenced. After the first layer is thus wound entirely from end to end another layer of asbestos 3 is laid' over the first winding and a similar winding is made around its outer surface from the other end back to the starting-point, the wire being continuous, and such operation is con tinued by adding additional intervening layers 3 and winding over them from one end to the other alternately until the final outer layer is wrapped with the last coil of wire, as shown at the rightof Fig. 2, when the wire is led outwardly beyond the end opposite to the starting-point, terminating in terminals 5. The wrappingwire is preferably comparatively fine wire. The terminals 4 and 5 are considerably heavier sections, providing suitable connecting-terminals for the terminals of the branch circuit leading from the highvoltage main-current wire. After being so wound the entire resistance is then surrounded on the inner and outer sides at each end by an inclosing substance 6, as plaster-ofparis, clay, porcelain, glass, or any other suitable fireproof material, which provides an impervious covering for the Wire and asbestos ger of short-circuiting or destruction by heat is entirely prevented. This covering top is cast around the resistance'in a plastic condition by means of a suitable mold and when hardened entirely incloses the resistance, as I have described, and presents a neat and finished appearance, leaving the coil in shape for commercial use. If desired, the outside may be painted or varnished with any substance adapted to suitably color it, which also provides an impervious coating, which prevents the entrance of moisture to the interior.

As thus constructed my improved resistance may be attached to conductors of highpotential current, and the reduced current may be safely used for any purpose for which the low voltage is peculiarly adapted. By its use I avoid the necessity of batteries of any kind and am able to tap the ordinary electriclight circuit for supplying such low-potential current for any of the various uses for which it may be required.

The advantage of this invention will be appreciated by those skilled in the art, as it is much cheaper and simpler and requires no attention whatever after installation, thus rendering it more completely available than the ordinary batteries now in use.

Having described my invention, what I claim is 1. A resistance-coil consisting of one or more cylindrical layers olinsulating material, wound around with conducting-wire terminating in attaching-terminals, with a surrounding covering of an impervious substance, substantially as set forth.

2. A resistance-coil consisting of a plurality of cylindrical layers of insulating material, a central longitudinal air-passage therethrough, a conducting-wire wound around each layersuccessively, alternately from one end to the other whereby the successive wrappings of the wire are insulated from each other, terminating in attaching-terminals, substantially as set forth.

3. A resistance-coil consisting of a plurality of cylindrical layers of insulating material, a conducting-wire wound around each layer succesively, alternately from one end to the other, whereby the successive wrappings of the wire are insulated from ea ch other, terminating in attaching-terminals, and a surrounding covering of impervious substance through which the terminals extend, substantially as set forth.

4. A resistance-coil consisting of a plurality of cylindrical layers of insulating material, a conducting-wire wound around each layer successively,alternately from one side to the other, whereby the successive wrappings of the wire are insulated from each other, terminating in attaching-terininals, and a surrounding covering of impervious substance through which the terminals extend, and an outer coating of impervious substance laid over such substance, substantially as set forth.

Signed at Pittsburg, Pennsylvania, this 3d day of December, 1900.

FRANK OOMMINGE.

\Vitnesses:

JAS. J. MCAFEE, G. M. CLARKE. 

